Audio Control 2XS Owner's Manual

®

making good stereo sound better

®

®

22410 70th Avenue West • Mountlake Terrace, WA 98043

Phone [phone] • Fax [phone]

www.audiocontrol.com

© 1994 AudioControl , AudioControl is a division of Electronic Engineering and
Manufacturing, Inc. Revised 1998

All rights are reserved.
AudioControl, Performance Match, Making Good Stereo Sound Better, Concert

Series, 2XS, EQX, EQL, EQT, and MVC are all trademarks of Electronic Engineering
and Manufacturing, Inc.

This manual was designed and written during a few rare sunny weekends of
espressos and micro-brews in a really nifty place in the Pacific Northwest
surrounded by slugs and other creatures crawling out of the rainforest.

Printed in U.S.A
Specifications subject to change without notice. P/N 9130330

tm

Concert Series

Stereo Crossover with Subsonic Filter

Owner’s Enjoyment Manual

Congratulations!

You have just purchased the state-of-the-art autosound crossover - the
2XS. This crossover is incredibly adjustable, programmable, and most
importantly, the 2XS will make your car audio system sound better.
Whether you are a car audio soundoff competitor or just someone who
appreciates good sound, the 2XS will provide you with many hours of
enjoyment. Please take a moment to familiarize yourself with the many
features of the 2XS by reading this manual.

Features of the Concert Series 2XS:

• Two channel operation

• Precise 2-way 18dB/octave, programmable electronic crossover

• with a plug-in module

• Programmable Frequency Match (PFM) subsonic filter

• Balanced inputs

• On-board line driver for signal gain

• Output level controls

• Selectable ground isolation

• Optimum signal output indicator LEDs

• The finest quality - designed and built in America

®

®

making good stereo sound better

page 1

®

FEATURES

Programmable 18dB/Octave 2-way Crossover

The 2XS utilizes a sharp 18dB/octave state variable filter that
accurately separates your high and low frequencies. In addition, by using
plug-in resistor modules (for more info see the section on “Making Your
Own Crossover Module”), the two way electronic crossover in the 2XS
can be configured precisely in any multi-amplified system.

Programmable Frequency Match (PFM) Subsonic Filter

Subsonics are low frequency non-musical noises which are present in
most recordings and usually occur below the frequencies which human
ears can detect. This robs amplifier power, causes intermodulation
distortion, and may even cause speaker damage. Obviously you don’t
want your system to reproduce these nasty sounds, therefore, the 2XS
features an AudioControl exclusive, a sharp 18dB/octave Programmable
Frequency Match (PFM) subsonic filter. This PFM filter rolls off these
problem-causing frequencies before they get to your amplifiers. Since it
is programmable, you can install a PFM resistor module at the ideal low
frequency roll-off point(like the subwoofer enclosure tuning frequency or
the -3dB down point of your system), and get the best possible sound
from your system.

Line Driver

Every electronic component produces a small amount of noise. This
noise is the result of electrons bouncing into each other like pinballs.
Unfortunately, these noises add to the “noise floor” of your car audio
system and can end up as hissssss through your speakers. Fortunately,
the circuitry in the 2XS has been designed to provide signal gain. This
“gain” allows you to raise the signal above the hissssssing noise floor and
drive your amplifier better. This, my friend, is a good thing.

page 2 page 3

Selectable Ground Isolation

Ground loops and ground noises are constant threats to a quality car
stereo installation. Head unit manufacturers ground their products one
way while amplifier manufacturers may ground theirs differently.
Unfortunately, these differences can cause ground loops. The 2XS helps
you avoid these problems by providing selectable signal and power
grounds. Ground loops are now things of the past.

The Most Important Instruction of All

FILL OUT AND SEND IN YOUR WARRANTY CARD!

Also, it is crucial that you keep your invoice or sales slip, since it is
your only proof of purchase. If somebody takes your 2XS while you're
vacationing in Tahiti, insurance companies and law enforcement officials
will require some proof of ownership on your part.

For the highest possible product performance and the lowest possible

use of aspirin, nothing is better than a profes­sional system installation. Your AudioControl

Performance Match audio dealer has the

training and equipment necessary to install your

2XS and achieve the best possible sound out of

your system. However, if you are a die-hard do-

it-yourselfer, this manual will give you all of

the information you need to make music

with your 2XS.

Happy listening.

A BRIEF TOUR OF THE 2XS
The Outside

INPUTS: Lurking on the bottom left hand corner of the 2XS, you’ll

see two RCA-type audio inputs. These are the inputs which get their
signals from the outputs of your head unit or equalizer. The inputs are
balanced, which helps cancel the evil noise that may be radiating into
your system from your car’s electrical system.

OUTPUT JACKS: To the right of the input jacks you’ll find two

more pairs of RCA-type jacks. The first pair (on the left) is your high
frequency output and the pair on the right is your low frequency output.

OUTPUT LEVEL ADJUSTMENTS: These adjustments control the

2XS signal output to your power amplifiers. The circuitry provides
output level control to drive any power amplifier with up to 9.5 volts of
input signal, which helps achieve maximum signal to noise ratio. This is
a really good thing. Please note: the output of the 2XS is proportional to
the input it receives. At aproximately 5.6v the 2XS should produce its
rated 9.5v of output. Any less input voltage and the output will decrease.

OUTPUT STATUS LEDS
POWER: Indicates when the 2XS is turned on, (clever!)
3 VOLT: Lights up when there is 3 volts RMS present at the 2XSs

output jacks. This is more than enough to drive most amplifiers, so
check your amplifier’s owner’s manual to make sure the amp can handle it.

1 VOLT: Displays when there is 1 volt RMS present at the 2XSs

output jacks.

POWER CONNECTOR: A wonderful, removable connector that

allows you to hook up all of the power and turn-on wires for your 2XS in
the convenience of daylight, and then attach them in the dark recesses of
your trunk.

Outside View

2XS Concert Series

Inside View

2XS Concert Series

The Inside

PROGRAMMABLE CROSSOVER MODULE: This 14 pin resistor

module controls the crossover frequency. We install a 90Hz resistor
module at the factory. However, should your system design require
something different, they are easy to change. Different modules may be
purchased from your dealer or custom built yourself (for more info see
the section on “Making Your Own Crossover Module”).

PROGRAMMABLE FREQUENCY MATCH (PFM) MODULES:

This 14 pin module is the same type of module as the one in the
crossover module socket. However, the PFM is the bottom limit for the
low frequency output. It is set from the factory at 33 Hz.

GROUND ISOLATION SELECTOR: This feature allows you to

change the power supply ground isolation for different systems. When
your 2XS was shipped from the factory, the selector was put in the fully
isolated position(which we know is the best). Alas, not every other
manufacturer (or installer) devotes so much time and effort into getting
their grounds right. Therefore, we have provided other ground isolation
options to help if you have a ground loop noise (alternator whine) in your
system. Experiment with different settings if you run into this type of
problem. To change the settings, turn system off, carefully move the
black jumper from the center two pins (fully isolated) to either the top
two pins (200Ω) or the bottom two pins (ground). If neither position
eliminates the noise, read on.

INPUT GROUND ISOLATION JUMPER: These jumpers provide a

hard ground for the balanced input circuitry. Some head units or pre­amplifiers require this for optimum low noise operation. To change the
input ground isolation, use the 3 pin jumper located on the lower left
portion of the 2XS’s circuit board (near the input RCAs.) The unit is
shipped in the balanced input position. This should be optimum for most
applications. Should you feel the need to experiment however, feel free
to turn the system off, change the jumper position and see if it helps.

page 4 page 5 page 6 page 7

INSTALLATION EXAMPLES AND HOOKUP DIAGRAMS -

Simple 2-channel, 2 Way System

2-Channel, 3 Way System

2-channel, 2 Way with the Epicenter and Equalization

QUICK REFERENCE GUIDE TO INSTALLING THE 2XS

If you can install a power amplifier or speakers, you won’t have any
trouble installing the 2XS. Two cables in, four cables out, connect the
power, ground, & remote turn-on and you’re in business. If this is a little
more than you can swallow in one sitting, read on because we’ve gone
ahead and talked each individual facet of the 2XS to death. You don’t
have to read it, but it will help you understand some of the more
sophisticated features of the 2XS.

MOUNTING: The 2XS can be mounted in many parts of the car,
depending on the vehicle’s configuration. Behind the dash, under a seat
and in the trunk are possibilities, in increasing order of distance from the
head end. The farther away, the greater the resistance in the cables,
which can cause signal or power loss. Use 100% shielded cables for the
best results. Wherever you mount the 2XS, take the following into
consideration:

* Don’t mount it near heaters, closed spaces or other places where

it will get really hot.

* The mounting location must be safe from water or beer seepage.
* The 2XS must be firmly mounted to the car. This

protects connections from breakage and stress as well as the
possibility of it becoming un-attached when you blast over the
occasional speedbump.

* Analyze the potential location carefully to make sure that

mounting screws won’t pierce a gas tank, gas/brake/or electrical
lines.

* The 2XS has been designed with very high quality

parts and in a manner which reduces mass-related circuit board
stress (a typical failing of lots of car gear). Still, all electronics
have a limit to environmental stress, so no fair mounting it to the
front bumper or under the oil pan.

AUDIO WIRING: The main idea is to minimize potential signal
interference and noise. That means using good quality 100% shielded
audio-type RCA cables. Since the 2XS has a very low output impedance,
cable noise pick-up OUT of the 2XS is not a problem.

The head unit that feeds the 2XS however, could have a medium
output impedance (2k to 10k ohms) and long cable lengths could be a
problem. That’s why we suggest mounting the 2XS as close as possible
to the head unit. The cables going from the deck to the 2XS must be the
best you can get. Not cheapo stranded shield with 50% shielding. Try to
hold out for the trusty 100% shielding to cut noise in this critical run. Of
course, if you are utilizing the balanced input circuitry in the 2XS, this
will also minimize your chance of noise.

POWER WIRING: The 2XS’ +12 volt and ground (-) connections
should be made with 18 gauge wire or better. Just insert the wire into
the nifty connector and tighten the screw.

page 8

NOTE: As always, you should disconnect the negative terminal of the

car’s battery before working on electrical connections.....Unless you want

an extra tingle in your day.

GROUNDING THE SOURCE UNIT BEHIND THE DASH AND
EVERYTHING ELSE TO THE FRAME IN THE REAR ALMOST
CERTAINL Y GUARANTEES THAT YOU WILL HAVE A GROUND
LOOP. USE A SINGLE GROUND POINT THAT YOU KNOW IS
COMMON WITH OTHER GROUNDED PARTS OF THE STEREO
SYSTEM. TO MINIMIZE NOISE, MAKE THE CONNECTION WITH
NO LESS THAN 18 GAUGE MUL TI-STRANDED WIRE.

OUTPUT LEVEL CONTROLS: These controls provide two useful
functions. First they allow you to control the overall balance between the
high frequency output and the low frequency output. Second they can
provide extra signal gain or cut if needed. Many head units have very
weak output levels - in this case both controls can be operated on the
“max” side. If the output is extremely high you can operate the controls
on the “min” side to match hi/low balance as well as to match overall
levels to the power amps.

CROSSOVER FREQUENCY SELECTION

We recommend that the crossover frequency be based on the design
criteria of the low and high frequency speakers. For example, a 2-way
system with 12" woofers for low frequencies and 5 ¼" 2-way separates for
midrange and high frequencies should utilize a crossover point based on
how low the 5 ¼" and how high the 12" will play.

Design for the system, not the woofers alone. We designed the 2XS
with a fixed but PROGRAMMABLE crossover. This is the most reliable
and accurate design. It will not change frequencies over time the way
knob adjustable crossovers will, and that is a really good thing.

MAKING YOUR OWN CROSSOVER MODULE

We have provided the 2XS with a 90Hz resistor module, ALREADY
PLUGGED IN. This is a common mid/treble dedicated woofer crossover
point.

Additional crossover and PFM filter modules are available from your
authorized AudioControl dealer. If you are good with a soldering iron you
can build your own modules by using the following formula:

7200
Selected Frequency(Hz)

= Resistance Value (in Kilohms)

Example: For a 2500Hz module, the formula yields a resistor value of
7200 ÷ 2500=2.88Kohms.
The 18dB crossover module requires six resistors of this value.

Note: Center remains open

NOTE: The resistors used must be ¼ watt and at

least 5% tolerance carbon film, or 1% tolerance metal film.

page 9

A BLATANT PLUG FOR OTHER AUDIOCONTROL PERFORMANCE
MATCH PRODUCTS

The 2XS is only one component in the AudioControl Performance Match
line designed to extract “killer” performance from your car stereo system.
Basically, there are real world barriers to good auto sound such as the fact that
doors and trunks rarely make good speaker boxes. AudioControl Performance
Match products, like the Concert Series 2XS, EQX

tm

, EQLtm, EQTtm, and the
new MVCtm (Master Volume Control) allow you to adjust or “voice” compo­nents to the specific acoustics and equipment in your stereo system whether it
is a sleek Honda or a stylish Buick. The result is, as one warranty card stated;
“A dream come true.”

THE AUDIOCONTROL CONCERT SERIES 2XS
LIMITED WARRANTY

People are scared of warranties. Lots of fine print, lots of non-cooperation,

months of waiting around. . .

Well don’t be scared of this warranty. It’s designed to make you rave about
us to your friends. It’s a warranty that looks out for you and helps you resist
the temptation to have your friend who is “good with electronics” try to repair
your AudioControl 2XS. So go ahead and read through this warranty, then
enjoy your new component for a few days before sending in the warranty card
and comments.

“Limited” doesn’t mean anything ominous. The Federal Trade Commission
tells all manufacturers to use the term to indicate certain conditions have to be
met before they’ll honor the warranty. IF you honor these conditions, we will
warrant all material and workmanship on your Concert Series 2XS for FIVE
YEARS from the date of purchase if installed by an authorized AudioControl
dealer, and will fix or replace it, at our option, during that time. For you “do­it-yourselfers”, we offer you the same warranty for one year.

Here are the conditions that make this warranty conditional:

1. You have to fill out the warranty card and send it to us within 15 days

after you purchased your 2XS.

2. You must keep your sales slip or receipt so you have proof of when and
where you bought your 2XS. We’re not the only company to require this, so
it’s a good habit to be in with any stereo purchase.

3. Your 2XS has to have been originally purchased from an authorized
AudioControl dealer. You do not have to be the original owner to take
advantage of the warranty, but the date of purchase is still important so be
sure to get a copy of the sales slip from the original owner.

4. You cannot let anybody who isn’t; (a) The AudioControl Factory;
(b) an authorized service center; or (c) someone authorized in writing by
AudioControl, service your 2XS. If anyone other than (a), (b), or (c) messes
with your 2XS, that voids the warranty.

5. The warranty is also void if the serial number has been altered or
removed, or if the AudioControl 2XS is used improperly. Now, that sounds
like a big loophole, but here is all we mean by it; unwarranted abuse is: (a)
Physical damage (our mobile products are not meant to be used as jack stands
for your car): (b) Improper connections. We have done the best we can to
protect the inputs. However, 120 volts into the input jacks can fry the innards
of the poor beasty: (c) Sadistic things. This is the best mobile product we
know how to manufacture, but if you use it for the front bumper of your Baja
bug and get it full of water and dirt, things will go wrong.

page 10 page 11

Assuming you conform to numbers 1-5, and it isn’t all that hard to do,
we get the option of deciding whether to fix your old unit or replace it with
a new one.

LEGALESE SECTION

This is the only warranty given by AudioControl. This warranty gives
you specific legal rights which vary from state to state. Promises of how
well your 2XS will work are not implied by this warranty. Other than what
we’ve covered in this warranty, we have no obligation, expressed or
implied. Also, we will not be obligated for direct or indirect consequential
damage to your system caused by hooking up the AudioControl 2XS.

Failure to send in a properly completed warranty card negates any
service claim.

2XS SPECIFICA2XS SPECIFICA

2XS SPECIFICA

2XS SPECIFICA2XS SPECIFICA

TIONSTIONS

TIONS

TIONSTIONS

All specifications are measured at 14.4 VDC
(standard automotive voltage)

Frequency Response......................................................... 15Hz-20kHz;±1dB

Total Harmonic Distortion (25Hz-20kHz) ......................................... 0.005%

Signal to Noise Ratio (rated full output) ............................................. 115dB

Maximum Output Level................................................................... 9.5 Vrms

Crossover Slope......................................................................... 18dB/Octave

Crossover type .......................................................................... State Variable

Crossover frequencies ................................ set at 90Hz (

user programmable)

PFM filter slope ......................................................................... 18dB/Octave

PFM filter frequency..................................set at 33Hz (user programmable)

Power supply .......................... transformer isolated PWM DC/DC converter

Power draw.......................................................................................... 150mA

Recommended fuse rating.................................................................... 1 Amp

Size ..........................................................................1.15"h x 5.5"w x 4.65"d

Weight ...................................................................................................... 2 lbs

Balanced In................................................................................................. yes

Input Ground Isolation jumpers ................................................................. yes

Output Ground Isolation jumpers .............................................................. yes

Country of Origin .................................................................................. U.S.A

2XS BL2XS BL

2XS BL

2XS BL2XS BL

OCK DIAGRAMOCK DIAGRAM

OCK DIAGRAM

OCK DIAGRAMOCK DIAGRAM